1. Field of the Invention
The present invention is directed to the processing of shrimp, and more particularly to a device and method which will process freshly chill-killed shrimp to decapitate the same and remove the thoracic plate as well as the pleopods so that the balance can be frozen or otherwise processed.
2. Summary of the Prior Art
Shrimp after they are caught must be decapitated within a relatively short period of time, or otherwise under even the best of conditions including freezing, decay can begin. The decapitation of shrimp has been largely a hand process normally eschewed by most human beings. Also the decapitation of shrimp by even a skilled operator takes considerable time.
These problems were realized and addressed by applicant earlier, and resulted in U.S. Pat. Nos. 3,309,731 and 3,408,686. Both patents were directed to a device for decapitating shrimp by means of bending the shrimp quickly around an edge or anvil as the shrimp's transition from a vertical tube with slow speed fluid to a horizontal tube with high speed fluid.
One of the drawbacks of the prior-art devices shown and described in U.S. Pat. Nos. 3,309,731 and 3,408,686 was the inability to positively orient the shrimp at all times so that they were presented to the decapitating chamber tail first, and more particularly with the legs facing the edge or anvil and the outer shell remote from the edge or anvil. Also the prior-art devices were susceptible of jams, and difficult to clean out quickly. Finally, according to the prior art, the heads and tails were separated through an essentially flotation method which required considerable space, and also was not totally reliable.
Additional prior art is exemplified by U.S. Pat. No. 3,576,047. In that patent, however, no means is provided for backwashing the shrimp in the event of a clog, and all of the processing presupposes that the shrimp have been put into individual carrier troughs referred to as distributor chutes 14. Similarly, U.S. Pat. No. 4,054,970 shows V-shaped members, but not the process of orienting all tail first prior to hydraulic decapitation. Neither of U.S. Pat. Nos. 3,576,047 or 4,054,970 disclose a total hydraulic technique for singulating and orienting.